8th Grade · Geometry
Cylinder
8.G.C.9
Definition
A three-dimensional solid with two parallel circular bases connected by a curved surface. Its volume equals pi times the radius squared times the height.
Examples
- V = π(3)²(5) = 45π ≈ 141.4 cubic units.
- Volume = area of the circular base times height.
Key rule
Cylinder volume is the circular base area times the height.
Memory hook
Circle base, straight up, times height.